Examples of using php magic methods

Some functions called Magic methods in PHP are introduced here: In fact, in general applications, we all need to use them! !

After PHP5.0, php object-oriented commissions more methods, making php more powerful! !
Some functions called magic methods in PHP are introduced here: In fact, in general applications, we all need to use them! !

1.construct() When instantiating an object, this method of the object is first called.
Java code
class Test { function construct() { echo "before"; } } $t = new Test();
class Test { function construct() { echo "before"; } } $t = new Test();
The output is:
start
We know that the php5 object model and the function with the same class name are the constructor of the class, then if we simultaneously If you define a constructor and construct() method, php5 will call the constructor by default instead of the construct() function, so construct() serves as the default constructor of the class
2.destruct() When deleting a This method is called when the object or object operation terminates.
Java code
class Test { function destruct() { echo "end"; } } $t = new Test(); will output end
class Test { function destruct() { echo "end"; } } $t = new Test(); will output end
We can then perform operations such as releasing resources at the end of the object operation
3.get() When trying Called when reading a property that does not exist.

If you try to read a property that does not exist in an object, PHP will give an error message. If we add a get method to the class, we can use this function to implement various operations similar to reflection in Java.
Java code
class Test { public function get($key) { echo $key . " does not exist"; } } $t = new Test(); echo $t->name; will output: name does not exist
class Test { public function get($key) { echo $key . "Does not exist"; } } $t = new Test(); echo $t->name; will output: name does not exist Exists
4.set() is called when trying to write a value to a property that does not exist.
Java code
class Test { public function set($key,$value) { echo 'pair'.$key . "attached value".$value; } } $t = new Test() ; $t->name = "aninggo"; will output: value attached to name aninggo
class Test { public function set($key,$value) { echo 'pair'.$key . "value attached" .$value; } } $t = new Test(); $t->name = "aninggo"; will output: append value to name aninggo

5.call() when trying This method is called when calling a method on an object that does not exist.
Java code
class Test { public function call($Key, $Args) { echo "The {$Key} method you want to call does not exist. The parameters you passed in are:" . print_r( $Args, true); } } $t = new Test(); $t->getName(aning,go);
class Test { public function call($Key, $Args) { echo "You want to call The {$Key} method does not exist. The parameters you pass in are: " . print_r($Args, true); } } $t = new Test(); $t->getName(aning,go);
The program will output:
Java code
The getName method you want to call does not exist. The parameters are: Array
(
[0] => aning
[1] => go
)
The getName method you want to call does not exist. The parameters are: Array
(
[0] => aning
[1] => go
)
6.toString() is used when printing an object Call
This method is similar to java's toString method. When we print the object directly, we call this function
class Test { public function toString() { return "Print Test" ; } } $t = new Test(); echo $t;
When echo $t; is run, $t->toString(); will be called to output
Print Test
7.clone() is called when the object is cloned
class Test { public function clone() { echo "I was copied!"; } }$t = new Test(); $t1 = clone $t;Program output: I have been cloned!

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